<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 6.00.2800.1170" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY bgColor=#ffffff> <DIV><FONT face=Arial size=2>Hi Bob,</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>You are right -- total noise = exposure.  There's a tradeoff between dB SPL and total duration of noise = exposure.  Lower noise levels can be tolerated for longer periods.  Very high = noise levels can be tolerated only briefly.  It's all laid out by OSHA at = the following URL:</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2><A href="http://www.osha.gov/SLTC/noisehearingconservation/index.html">htt= p://www.osha.gov/SLTC/noisehearingconservation/index.html</A></FONT></DIV= > <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>Somewhere amongst all their = documentation is a handy table of dB SPL vs. duration of exposure.</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>Peace,</FONT></DIV> <DIV><FONT face=Arial size=2>Sarah</FONT></DIV> <BLOCKQUOTE style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; = BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px"> <DIV style="FONT: 10pt arial">----- Original Message ----- </DIV> <DIV style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: = black"><B>From:</B> <A title=hullfam5@yahoo.com href="mailto:hullfam5@yahoo.com">Bob = Hull</A> </DIV> <DIV style="FONT: 10pt arial"><B>To:</B> <A = title=pianotech@ptg.org href="mailto:pianotech@ptg.org">Pianotech</A> </DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, August 16, 2003 = 11:43 AM</DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: "Put a plug in = it"</DIV> <DIV><BR></DIV> <DIV>Isn't it not only the level of dbs but the duration of the sound = that is important in causing damage to your hearing?  There is a = cumulative effect on your ears. For instance their is a length of = time that you can withstand the sound level of a lawnmower per day = before hearing damage is likely.  I always wear hearing protection to = mow, run the leafblower and many things in the shop.   Since the = length of the sound we hear at 100 dbs or so is short while tuning I wonder if = the cumulative effect is enough to damage our hearing.  </DIV> <DIV> </DIV> <DIV>Bob Hull<BR><BR><B><I>Richard Oliver Snelson <rsnelson@bwsys.net></I></B> wrote:</DIV> <DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px = solid; WIDTH: 100%"><BR>I did some sound level measurements on several pianos in my shop = this<BR>week. The DB meter was held at about the distance my ear would be = from<BR>the strings and soundboard. Using solid rather strong blows I = measured<BR>sound levels well over 100 dbs on both grands and uprights. <BR><BR>What = started this was the testing trick with the fingers that = someone<BR>mentioned a few weeks ago. For the last year I've had problems setting<BR>the = unisons on G7. Having to turn my head to focus and hear them. Turns<BR>out I've got = quite a bit of hearing loss at that frequency and above, in<BR>my left ear. = Turning my head allowed me to compensate for it with the<BR>better right = ear. At 67 years old, I'm not too surprised at the loss in<BR>my left ear. = However I'm sure that it's come on quite quickly. Several<BR>hours a day = pounding out tunings has made it worse. As a result I'm not<BR>! only carrying = ear plugs, I'm using them. I tell the customer they help<BR>to filter out noise = that I don't need to hear. I do take them out of my<BR>ears when I reach = the last octave, for the unisons there. There seems to<BR>be a difference in = the brightness of the sound when taking the plugs out<BR>at that time. = I'm sure it's a result of not having the previous 45 mins<BR>to 1 hr of 100 = db plus sound levels thumping on my eardrums. <BR><BR>I thought you might = like to know about the 100 db plus levels...<BR>Regards to all. Rich<BR>_______________________________________________<BR>pianotech = list info: = https://www.moypiano.com/resources/#archives</BLOCKQUOTE></DIV> <P> <HR SIZE=1> Do you Yahoo!?<BR><A = href="http://us.rd.yahoo.com/evt=10469/*http://sitebuilder.yahoo.com"= >Yahoo! SiteBuilder</A> - Free, easy-to-use web site design software</BLOCKQUOTE></BODY></HTML>